Eating disorders cause a number of severely impairing symptoms that may require more intensive intervention that is available through outpatient therapy services. The PHP/IOP level of care may be an effective mode of treatment in these cases, but few studies have examined overall outcomes or treatment moderators for this level of care. Using a large sample from a PHP/IOP specifically designed for the treatment of eating disorders, the current study examines a variety of symptoms (eating disorder severity, quality of life, depression, etc.) from admission to discharge, as well as potential moderators of treatment, including demographic and clinical factors. Overall, the PHP/IOP level of care was found to improve treatment outcomes. Age, race, gender, and depression were found to moderate the change in quality of life and functional impairment. Additionally, patients diagnosed with anorexia nervosa had significantly lowered quality of life and greater eating disorder symptomatology than all other diagnoses. The results of this study can help to inform clinical practice and help guide in treatment decisions at the partial hospitalization level of care.